KR20100005659A - Pneumatic tire, tire mold, and method of manufacturing pneumatic tire - Google Patents

Abstract

PURPOSE: A pneumatic tire, a tire mold, and a manufacturing method of the pneumatic tire are provided to improve the steering performance on a snow or icy road by reducing a bent hole and to reduce the manufacturing defect by using a concave part, a rising portion, and an indent/lug. CONSTITUTION: A pneumatic tire(1) is composed of a tread(2), a concave part or rising portion(62), and a first indent/lug. The tread is formed of plural lateral grooves of the tire. The tread comprises a land part(23) and a sipe. The concave part or rising portion is formed on the lateral side of the land part. The first indent/lug is formed on the bottom of the concave part, the top of the rising portion, or the lateral side of the land part.

Description

PNEUMATIC TIRE, TIRE MOLD, AND METHOD OF MANUFACTURING PNEUMATIC TIRE}

The present invention relates to a pneumatic tire, a tire mold, and a manufacturing method of a pneumatic tire for improving rotational performance on ice roads and snow roads.

Pneumatic tires, particularly pneumatic tires that are desirable on ice and snow, can achieve rotational performance by removing the water film generated between the road surface and the tread surface. Known conventional pneumatic tires comprise a zig-zag shaped sipe, as shown above, and a small groove of shorter depth than the sipe, all of which are provided on land surfaces comprising a plurality of blocks. In such a conventional pneumatic tire, a small sipe removes the water film generated between the road surface and the tread surface, thereby achieving excellent rotational performance on an icy road surface and a snow covered road surface (see, for example, Japanese Patent No. 3702958). ).

In the pneumatic tire for ice and snow, the shoulder-shaped land portion located in the outermost layer portion in the tire width direction is deformed due to the load applied across the tire width direction when the vehicle rotates. As a result, the side of the land portion comes into contact with the road surface. In order to achieve the rotational performance, it is necessary to remove the water film generated between the side surface of the land portion and the road surface.

It is an object of the present invention to at least partially solve the problems of the prior art.

A pneumatic tire according to an aspect of the present invention is formed in a land portion divided by a plurality of circumferential grooves extending in a tire circumferential direction and a plurality of widthwise grooves extending in a tire width direction and a contact patch of the land portion. A tread comprising a sipe, which is formed in the tire widthwise side of the land portion provided in the outermost portion of the tire width direction so as to be connected to the widthwise groove, and the indents / lugs are alternately or continuously arranged in a linear manner And a first indent / lug provided on the bottom surface of the recess, the top surface of the raised portion, or the tire widthwise side surface of the land portion.

In the pneumatic tire, the recessed portions may each have a recess depth d set in a range of 0.3 mm ≦ d ≦ 3.0 mm with respect to the tire widthwise side surface of the land portion, and the raised portions may each have a tire widthwise side surface of the land portion. May have a raised height h set in the range of 0.3 mm ≦ h ≦ 3.0 mm, wherein the first indents / lugs each have a diameter of 0.1 mm ≦ di ≦ between the tire widthwise side of the land portion and the indent or lug. Have a difference (di) set in the range of 2.0 mm, the pitch p of the lug set in the range 0.3 mm ≤ p ≤ 3.0 mm, and the width s of the indent set in the range of 0.1 mm ≤ s ≤ 1.5 mm It may be.

In the pneumatic tire, the concave portion may be formed to contact the contact patch of the land portion provided at the outermost part in the tire width direction.

The pneumatic tire may further include a second indent / lug in the contact patch of the land portion at the outermost side in the tire width direction. The second indent / lug may be in communication with the bottom surface of the concave portion formed to contact the contact patch of the land portion, or the first indent / lug formed on the tire widthwise side surface of the land portion.

In pneumatic tires, the first indents / lugs formed on the bottom surface of the concave portion, the upper surface of the raised portion, or the tire widthwise side surface of the land portion are formed at a predetermined distance from the outer circumference of this surface where the first indents / lugs are formed. May be

In a pneumatic tire, the recess or the raised portion is formed to extend, and may be inclined with respect to the normal to the tire circumferential direction.

In the pneumatic tire, the recessed portion or the raised portion may have an inclination angle θ set in a range of 5 ° ≦ θ ≦ 60 ° with respect to a tangent in the tire circumferential direction.

In pneumatic tires, each of the recesses or risers may be formed to have an acute end oriented in the tire rotation direction.

In a pneumatic tire, the first indent / lug formed on the bottom surface of the recess, the upper surface of the raised portion, or the tire widthwise side surface of the land portion is an angle set in a range of 0 ° ≦ α ≦ 60 ° with respect to the tire radial direction. It may have (α).

In pneumatic tires, the sipe may be formed in a zigzag shape for use on ice and snow roads.

A tire mold according to another aspect of the present invention includes a tread molding portion in which a tread of a pneumatic tire according to the present invention is formed.

According to still another aspect of the present invention, there is provided a method of manufacturing a pneumatic tire, comprising: forming a raw tire, mounting a raw tire to a tire mold according to the present invention, and extending a tire into a tire radially outward. Attaching the green tire to the heating, and heating the green tire to cause vulcanization.

The above and other objects, features, advantages and technical and industrial meanings of the present invention will become better understood upon reading the following detailed description of the presently preferred embodiments of the invention when considered in conjunction with the accompanying drawings.

The pneumatic tire according to the invention can achieve rotational performance by removing the water film generated between the road surface and the tread surface, especially on ice roads and snow roads.

Representative embodiments of the pneumatic tire, the tire mold, and the manufacturing method of the pneumatic tire according to the present invention are described below with reference to the accompanying drawings. This invention is not limited to embodiment. The components of an embodiment include the elements available to those skilled in the art, or are substantially the same as in the prior art. The plurality of modifications described in the embodiments may be arbitrarily combined within the scope of self-evident for those skilled in the art.

1 is a partial plan view of a tread of a pneumatic tire according to an embodiment of the present invention. FIG. 2 is a sectional view of the pneumatic tire shown in FIG. 1. 3 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1. 4 is an enlarged cross-sectional view taken along line IV-IV of FIG. 3. 5 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1. FIG. 6 is an enlarged cross-sectional view taken along VI-VI of FIG. 5. 7 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1. 8 is an enlarged cross-sectional view taken along the line VIII-VIII in FIG. 7. 9 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1. FIG. 10 is an enlarged cross-sectional view taken along the line VIII-VIII in FIG. 9. FIG. 11 is an enlarged view of a portion D shown in FIG. 3. 12-15 are partially enlarged perspective views of the tread of the pneumatic tire shown in FIG. 16 is a table showing a result of a performance test of a pneumatic tire according to the embodiment of the present invention.

As used herein, the tire width direction means a direction parallel to the rotational axis (not shown) of the pneumatic tire 1. The inner side in the tire width direction used herein means a portion near the tire equatorial plane (C) in the tire width direction, and the outer side in the tire width direction used here is the tire equator plane (in the tire width direction). C) It means the part far from. As used herein, the tire radial direction means a direction perpendicular to the axis of rotation. As used herein, the inner side of the tire radial direction means a portion close to the rotation axis of the tire radial direction, and the outer side of the tire radial direction used herein means a portion away from the rotation axis of the tire radial direction. As used herein, the tire circumferential direction means the circumferential direction around the rotation axis serving as the central axis. As used herein, the tire equator plane C means a plane perpendicular to the rotational axis of the pneumatic tire 1 and passing through the center of the tire width of the pneumatic tire 1. As used herein, a tire equalization line means a line in the tire equator plane C and extending along the circumferential direction of the pneumatic tire.

The pneumatic tire 1 according to the present embodiment is a pneumatic radial tire such as a winter tire or a four season tire used on an ice road and a snow road, and includes a tread 2.

As shown in FIG. 1, the tread 2 is made of rubber material and exposed to the outside of the pneumatic tire 1, the surface of which is contoured to the pneumatic tire 1. The tread 2 includes a plurality of circumferential grooves 21 extending in the tire circumferential direction, a plurality of widthwise grooves 22 extending in the tire width direction, and a circumferential groove 21 and a widthwise groove 22. A land portion 23 divided by is provided. A plurality of sipes 231 of small grooves are formed on the surface of the land portion 23, that is, the contact patch 23a which comes into contact with the road surface during travel. The sipe 231 generates an edge effect by biting the road surface of the ice road and the snow road, thereby providing a grip to the land portion 23. This is to affect the braking performance and the handling stability on the ice and snow road. In the present embodiment, the sipe 231 is formed in a zigzag shape for use on an ice road and a snow road. The sipe 231 is not limited to a zigzag shape and may be formed to extend in the tire width direction in a linear manner although not shown.

As shown in Fig. 2, shoulder portions 3 are provided on both outer sides of the tread 2 in the tire width direction. Inside the shoulder portion 3 in the radial direction of the tire, there is a side wall 4 exposed at the outermost part of the pneumatic tire 1 in the tire width direction. Inside the tire radial side wall 4 is a bead 5 mounted to a rim (not shown). Inside the pneumatic tire 1, although not shown, a carcass that forms the structure of the tire is placed so as to form an annular shape across the tread 2 to the bead 5. A reinforcing belt is provided on the outer circumference of the carcass of the tread 2.

In the pneumatic tire 1, the tire widthwise side surface 23b of the land portion 23, which is provided at the outermost part (shoulder portion 3) in the tire width direction, is connected to the inner surface of the widthwise groove 22. And the concave portion 61 or the raised portion 62 formed so as to be formed.

The recess 61 includes a groove-bottom recess A611 in contact with the groove-bottom of the widthwise groove 22 and a groove-top recess B612 in contact with the tread opening of the widthwise groove 22. do. As shown in FIGS. 3 to 6, two land portions 23 contacting a portion of the groove-bottom of the widthwise groove 22 and engaging each other in the circumferential direction with each widthwise groove 22 therebetween. Groove-bottom recess A611 is provided to extend across. On the contrary, as shown in Figs. 3 to 10, the groove is in contact with a part of the opening of the widthwise groove 22 and also in contact with a part of the contact patch 23a of the land portion 23 of the outermost part in the tire width direction. Upper concave portion B612 is formed.

As shown in Figs. 7 to 10, as in the groove-bottom recess A611, abuts the groove-bottom of the widthwise groove 22 and therebetween in the direction of each widthwise groove 22 and tire circumference. Rise 62 is provided to extend across two land portions 23 that engage each other.

Bottom surface of the recess 61 (groove-bottom recess A611, groove-top recess B612), upper surface of the rise portion 62, or tire widthwise side surface 23b of the land portion 23. Indents / lugs 7 are formed in the grooves. Indents / lugs 7 are provided to have either indents or lugs for these surfaces. These indents / lugs are formed alternately and continuously. The indents / lugs 7 run in a direction inclined with respect to the tire radial direction. 4, 6, 8 and 10 show indents / lugs 7 with lugs from the surface.

3 and 4 show an indent / lug 7 formed in the bottom surface of the recess 61 (groove-bottom recess A611, groove-top recess B612). 7 and 8 show the indents / lugs 7 formed on the bottom surface of the recess 61 (groove-top recess B612) and the upper surface of the rise 62. 5 and 6 show indents formed in the tire widthwise side surface 23b of the land portion 23, in which a recess 61 (groove-bottom recess A611, groove-top recess B612) is provided. / Lug 7 is shown. 9 and 10 also show indents formed in the tire widthwise side surface 23b of the land portion 23, in which the recess portion 61 (groove-upper recess B612) and the rise portion 62 are provided. / Lug 7 is shown.

In the pneumatic tire 1, the land portion 23 in the tire width direction outermost portion is deformed due to the load applied across the tire width direction when the vehicle rotates, and the tire width direction of the land portion 23 is changed. Side 23b comes into contact with the road surface. Therefore, all of the recesses 61 (groove-bottom recesses A611, groove-top recesses B612), raised portions 62, and indents / lugs 7 provided on the tire width direction side surface 23b are all provided. ) Removes the water film generated between the road surface and the tire width direction side surface 23b. In particular, recesses 61 (groove-bottom recesses A611, recesses-upper recesses B612) and raised portions 62 are provided and connected with the widthwise grooves 22. Since the water between the road surface and the tire widthwise side surface 23b is discharged to the widthwise groove 22, the water film can be easily and quickly removed. Also, the indent / lug 7 increases the surface area to be in contact with water, thereby effectively removing the water film. This improves braking force and handling stability when the vehicle rotates on ice and snow.

In the pneumatic tire 1 according to the embodiment of the present invention, as shown in Figs. 4, 6, 8 and 10, each recess 61 (groove-bottom recess A611), groove The upper recess B612 has a recess depth d set in the range of 0.3 mm ≦ d ≦ 3.0 mm with respect to the tire widthwise side surface 23b of the land portion 23. As shown in Figs. 8 and 10, each rising portion 62 has a rising height h set in a range of 0.3 mm ≦ h ≦ 3.0 mm with respect to the tire widthwise side surface 23b of the land portion 23. Has As shown in FIGS. 4, 6, 8 and 10, each indent / lug 7 is; Difference between the indent or lug and the tire widthwise side surface 23b of the land portion 23b in the range of 0.1 mm ≤ di ≤ 2.0 mm, the pitch of the lug set in the range of 0.3 mm ≤ p ≤ 3.0 mm (p), and the width s of the indent set in the range of 0.1 mm ≦ s ≦ 1.5 mm. The pitch p of the lugs is the distance between the center points of adjacent lugs with each indent in between.

According to the arrangement, when the depth d of the recess 61 (groove-bottom recess A611, groove-top recess B612) or the height h of the rise 62 is less than 0.3 mm, The drainage effect is reduced. In contrast, when the depth d of the recess 61 (groove-bottom recess A611, recess-upper recess B612) or the height h of the rise 62 exceeds 3.0 mm, The stiffness of the tread 2 is reduced, reducing the handling stability. In addition, when the difference di of the indents / lugs 7 is less than 0.1 mm, the pitch p of the lugs exceeds 3.0 mm, and the width s of the indents exceeds 1.5 mm, a drainage effect Is reduced. In contrast, when the difference di of the indents / lugs 7 exceeds 2.0 mm, a mold lubricant (silicon or the like) easily enters the indents / lugs 7. Thus, although the mold lubricant facilitates the removal of the pneumatic tire from the tire mold during manufacture, the mold lubricant in the early stages of use of the pneumatic tire 1 deteriorates braking performance and handling performance. For this reason, the depth d of the recess 61 (groove-bottom recess A611, the groove-top recess B612), the height h of the rise 62, the indent / lug 7 By defining the difference di, the lug pitch p, and the indent width s, the rotational performance on the ice road and snow road is improved.

The depth d of the recess 61 (groove-bottom recess A611, groove-top recess B612) with respect to the tire widthwise side surface 23b of the land portion 23 is 0.3 mm ≦ d ≦ 2.0. It is preferable to set in the range of mm. The rising height h of the rising part 62 with respect to the tire width direction side surface 23b of the land part 23 is preferably set in the range of 0.3 mm ≦ h ≦ 2.0 mm. In the indent / lug 7, the difference di between the tire widthwise side surface 23b of the land portion 23 and the indent or lug is preferably set in the range of 0.1 mm ≦ di ≦ 0.4 mm, The pitch p of the lug is preferably set in the range of 0.5 mm ≦ p ≦ 1.5 mm, and the width s of the indent is preferably set in the range of 0.2 mm ≦ s ≦ 0.8 mm. As such, the depth d of the recess 61 (groove-bottom recess A611, the recess-top recess B612), the height h of the raised portion 62, and By defining the difference di of the indents / lugs 7, the pitch p of the lugs, and the width s of the indents, the rotational performance on the ice road and snow road is further improved.

In the pneumatic tire 1 according to the present invention, the groove-top concave portion B612 in contact with a part of the contact patch 23a of the land portion 23 in the tire width direction outermost portion is described above. It is provided as a recess 61.

According to this arrangement, the groove-top recess B612 provides an edge effect. This further improves rotational performance on ice and snow.

In the pneumatic tire 1 according to the present embodiment, the indent / lug 8 is the land portion 23 of the outermost part of the tire width direction as shown in FIGS. 3, 5, 7, and 9. Is formed in the contact patch 23a. Like the indent / lug 7, the indent / lug 8 is provided to have either an indent or a lug relative to the surface. Indents and lugs are formed alternately or continuously. The indent / lug 8 is a difference set between the contact patch 23a of the land portion 23 and the indent or lug in the range of 0.1 mm or more and 2.0 mm or less, 0.3 mm or more and 3.0 mm or less (preferably 0.5 pitch of the lug set in the range of not less than 1.5 mm) and indentation set in the range of 0.1 mm or more and 1.5 mm or less (preferably 0.2 mm or more and 0.8 mm or less). The indent / lug 8 extends in the direction inclined with respect to the tire width direction. As shown in FIG. 10, the indent / lug 8 is formed on the bottom surface of the recess 61 (groove-upper recess B612) or on the tire widthwise side 23b of the land portion 23. It is in communication with the dent / lug 7. In particular, the indent of the indent / lug 8 communicates with the indent of the indent / lug 7, and the lug of the indent / lug 8 communicates with the lug of the indent / lug 7.

According to this arrangement, the indent / lug 7 is in communication with the indent / lug 8 in the contact patch 23a of the land portion 23. Since water generated between the road surface to be contacted at the time of rotation of the vehicle and the tire widthwise side surface 23b is discharged to the indent / lug 8, the water film can be easily and quickly removed. This further improves rotational performance on ice and snow.

In the pneumatic tire 1 according to the present embodiment, the indents / lugs 7 are formed at a predetermined distance from the outer circumference of the surface where the indents / lugs 7 are formed. In particular, a flat portion 7a is provided along the outer periphery of the surface on which the indents / lugs 7 are formed (see FIGS. 12-15). In FIG. 12, the indent / lug 7 is formed on the bottom surface of the recess 61 (groove-bottom recess A611, groove-top recess B612), and the bottom of the recess 61. Along the outer periphery of the face a flat portion 7a is provided. In FIG. 13, indents / lugs 7 are provided on the tire widthwise side surface 23b of the land portion 23 while a recess 61 (groove-bottom recess A611, groove-top recess B612) is provided. ) Is formed. A flat portion 7a is provided along the outer circumference of the tire widthwise side surface 23b. In Fig. 14, indents / lugs 7 are formed on the bottom surface of the recess 61 (groove-upper recess B612) and the upper surface of the rise portion 62, and the outer periphery of the lower surface and the upper surface is formed. A flat portion 7a is thus provided. In FIG. 15, an indent / lug 7 is formed in the tire widthwise side surface 23b of the land portion 23 while the recess portion 61 (groove-top recess B612) and the rise portion 62 are provided. do. A flat portion 7a is provided along the outer circumference of the tire widthwise side surface 23b.

This arrangement prevents the reduction of the stiffness at the portion where the indents / lugs 7 are formed and prevents the cracking of the edges of the indents / lugs 7.

In the pneumatic tire 1 according to the present embodiment, the recess 61 (groove-bottom recess A611) or the raised portion 62 is formed to extend, and is inclined with respect to the normal to the tire circumferential direction. (See FIGS. 3 and 7).

According to the above arrangement, the recess 61 (groove-bottom recess A611) or the rise 62 is inclined with respect to the normal to the tire circumferential direction at an angle of rotation direction of the pneumatic tire 1. This produces an edge effect, further improving the rotational performance on ice roads and snow roads. The inclination with respect to the normal to the tire circumferential direction is such that the recess 61 (groove-bottom recess A611) or the end 6a of the rise 62 faces either the outside or the inside of the tire radial direction. You may lose.

The inclination angle θ of the recess 61 (groove-bottom recess A611) or the rise 62 with respect to the tangent line in the tire circumferential direction is preferably set in the range of 5 ° ≤θ≤60 °. By setting the inclination angle [theta] within this range, the water between the road surface and the tire widthwise side surface 23b, which is in contact at the time of rotation of the vehicle, can be effectively discharged to the widthwise groove 22. Further, the inclination angle θ is preferably 15 ° ≦ θ ≦ 30 in order to effectively discharge the water between the road surface and the tire widthwise side surface 23b, which is in contact with the rotation of the vehicle, to the widthwise groove 22. It is set in the range of °.

In the pneumatic tire 1 according to the present embodiment, the recess 61 (groove-bottom recess A611) or the riser 62 is formed to have an acute end 6a oriented in the rotational direction of the tire. (See FIGS. 3 and 7).

According to the arrangement, the acute angle of the end 6a increases the edge effect. This further improves rotational performance on ice and snow.

In the pneumatic tire 1 according to the present embodiment, the indent / lug 7 is 0 ° ≦ θ ≦ 60 ° with respect to the tire radial direction as shown in FIGS. 3, 5, 7 and 9. Has an angle α set in the range of.

According to this arrangement, by defining the angle α of the indent / lug 7 with respect to the tire radial direction, water between the road surface and the tire widthwise side surface can be effectively discharged. This further improves rotational performance on ice and snow. Further, by defining the angle α with respect to the tire radial direction, it is preferable that the rubber flows into the mold when the pneumatic tire 1 is molded. This reduces manufacturing defects, thus improving the productivity of pneumatic tires with good rotational performance on ice and snow.

The pneumatic tire 1 according to the present embodiment is molded in a tire mold including a tread molding portion in which a tread 2 can be formed (see FIGS. 1 to 5). In addition to the tire mold, recesses 61 (groove-bottom recesses A611, groove-top recesses B612), raised portions 62, indents / lugs 7, and indents / lugs 8 The tread molding portion in which) is formed may allow the rubber to flow preferably. This reduces manufacturing defects. In addition, since the rubber flows preferably, the vent hole is reduced, so that the work for removing the root-like portion formed by the vent hole is reduced. This improves the productivity of the pneumatic tire 1 having excellent rotational performance on ice roads and snow roads.

According to the manufacturing method of the pneumatic tire 1, a green tire (raw tire) in a forming machine (not shown) using materials for carcass, belt, tread, shoulder, side wall, and bead ) Is formed. The green tire is then mounted to a tire mold comprising a tread molding portion in which the tread 2 can be molded. The green tire is brought into contact with the tire mold while expanding tire radially outward. The green tires are heated, so that the rubber molecules of the tread and the sulfur molecules combine to generate vulcanization. During vulcanization, the tread portion of the raw tire is in the shape of a tire mold, so that the tread 2 of the pneumatic tire 1 is formed. Finally, the molded pneumatic tire 1 is taken out of the tire mold.

The manufacturing method of the pneumatic tire 1 enables the production of the pneumatic tire 1 having excellent rotational performance on ice roads and snow roads.

In the pneumatic tire 1 according to the present embodiment, as shown in FIGS. 7 to 10, 14, and 15, the recessed portion 61 (opening recessed portion 612) and the raised portion 62 are provided. A step is formed across the open concave portion 612 and the tire widthwise side 23b to the raised portion 62, and the step is gradually increased while moving away from the tire widthwise side 23b. According to this arrangement, the stairs increase the edge effect, further improving the rotational performance on the ice road and snow road.

According to this embodiment, the performance test was performed about the rotational performance on an ice road and snow road using the some kind of pneumatic tire of different conditions (refer FIG. 16).

Performance tests were conducted by attaching pneumatic tires with tire sizes 215 / 60R16 to the standard rim, applying standard internal pressure and standard load, and then applying the tires to a four-wheel test vehicle (2500 cc, front engine rear drive). By attaching to The standard rim is The Japan automobile tire manufacturers association, Inc. "Applicable rim" as specified by (JATMA), The tire and rim association, Inc. "Design Rim" as specified by (TRA), or "measuring rim" as specified by The European type and rim technical organization (ETRTO). Standard internal pressure refers to the "maximum air pressure" specified by JATMA, the maximum value of the "tire load limit at various cooling inflation pressures" specified by TRA, or the "expansion pressure" specified by ETRTO. The standard load refers to the "maximum load capacity" specified by JATMA, the maximum value of the "tire load limit at various cooling inflation pressures" specified by TRA, or the "load capacity" specified by ETRTO.

As an evaluation method, a performance test on rotational performance was conducted so that a test vehicle with pneumatic tires was driven in a circle of 30 m radius on both an ice road and a snow road, and the lap time was measured every time the vehicle traveled. The average of the lap times measured during the five-wheel drive was calculated on the ice and snow roads, respectively. Next, the measurement result was evaluated as an index value using the prior art example as the reference numeral 100. In this evaluation, a larger value is preferable.

The pneumatic tire of the prior art example has no recesses (groove-bottom recesses, groove-top recesses), raised portions, or indents / lugs. In contrast, the pneumatic tires of Example 1 all include well-formed groove-bottom recesses or raised portions, and indents / lugs outside the land portions. The pneumatic tire of Example 2 includes a groove-top recess in addition to the elements of Example 1. In the pneumatic tie of Example 3, the indents / lugs provided on the outside of the land portion communicate with the indents / lugs provided in the land contact patch, in addition to the elements of Example 2. In the pneumatic tire of the fourth embodiment, in addition to the elements of the third embodiment, an indent / lug outside the land portion is provided at a predetermined distance from the outer circumference of the surface thereof. In the pneumatic tire of Example 5, in addition to the elements of Example 4, the groove-bottom recess or the raised portion is inclined. In the pneumatic tire of Example 6, in addition to the elements of Example 5, the groove-bottom recess or riser has an acute end. The pneumatic tires of Examples 1 to 6 include a raised portion or a recess (groove-bottom recess) that forms an inclination angle θ set at 20 ° with respect to the tangential line in the tire circumferential direction.

As can be seen from the test results shown in FIG. 16, the pneumatic tires of Examples 1 to 6 have excellent rotational performance on ice roads and snow roads.

The pneumatic tire according to an aspect of the present invention includes a raised portion or a recess provided to be connected with the widthwise groove. When the vehicle rotates, water between the road surface and the tire widthwise side surface of the land portion is discharged to the widthwise groove, so that the water film can be easily and quickly removed. Indents / lugs also increase the surface area that will come into contact with water, effectively removing the water film. This improves rotational performance on ice and snow.

A tire mold according to another aspect of the present invention includes a recess, a rise portion, and a tread molding portion in which indents / lugs are formed. This allows the rubber to flow preferably, reducing manufacturing defects. In addition, since the rubber flows preferably, the vent hole is reduced, so that the work for removing the root-shaped portion formed by the vent hole is reduced. This improves the productivity of pneumatic tires with good rotational performance on ice and snow.

The method of manufacturing a pneumatic tire according to another aspect of the present invention enables the production of a pneumatic tire having excellent rotational performance on ice roads and snow roads.

Although the present invention has been described with respect to specific embodiments for a complete and specific description, the appended claims are not limited thereto and are intended to embody all improvements and alternative configurations that may occur to those skilled in the art within the basic teachings described herein. Can be configured.

1 is a partial plan view of a tread of a pneumatic tire according to an embodiment of the present invention.

FIG. 2 is a meridional cross section of the pneumatic tire shown in FIG. 1. FIG.

3 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

4 is an enlarged cross-sectional view taken along line IV-IV of FIG. 3.

5 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

FIG. 6 is an enlarged cross-sectional view taken along VI-VI of FIG. 5.

7 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

8 is an enlarged cross-sectional view taken along the line VIII-VIII in FIG. 7.

9 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

FIG. 10 is an enlarged cross-sectional view taken along the line VIII-VIII in FIG. 9.

FIG. 11 is an enlarged view of a portion D shown in FIG. 3.

12 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

FIG. 13 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1. FIG.

14 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

15 is a partially enlarged perspective view of the tread of the pneumatic tire shown in FIG. 1.

16 is a table showing a result of a performance test of a pneumatic tire according to the embodiment of the present invention.

Claims (12)

A tread comprising a land portion formed and divided by a plurality of circumferential grooves extending in the tire circumferential direction and a plurality of widthwise grooves extending in the tire width direction and formed in a contact patch of the land portion, A concave or raised portion formed in the tire width direction side of the land portion provided in the tire width direction outermost portion so as to be connected to the width direction groove; A pneumatic tire comprising a first indent / lug provided on the bottom surface of the recess, the top surface of the raised portion, or the tire widthwise side of the land portion such that the indents / lugs are alternately or continuously arranged in a linear manner. The method of claim 1, The recesses each have a recess depth d set in a range of 0.3 mm ≦ d ≦ 3.0 mm with respect to the tire widthwise side surface of the land portion, The rising portions each have a rising height h set in a range of 0.3 mm ≦ h ≦ 3.0 mm with respect to the tire widthwise side surface of the land portion, The first indent / lug is a difference (di) set in a range of 0.1 mm ≤ di ≤ 2.0 mm, and a lug set in a range of 0.3 mm ≤ p ≤ 3.0 mm, respectively, between the tire widthwise side surface of the land portion and the indent or lug. A pneumatic tire having a pitch p and a width s of indents set in a range of 0.1 mm ≦ s ≦ 1.5 mm. The pneumatic tire according to claim 1, wherein the concave portion is in contact with a contact patch of the land portion provided at the outermost side in the tire width direction. The tire of claim 1, further comprising a second indent / lug in the contact patch of the land portion at the outermost portion of the tire width direction, The pneumatic tire in communication with the second indent / lug communicates with the bottom surface of the recess formed to contact the contact patch of the land portion, or the first indent / lug formed on the tire widthwise side surface of the land portion. The first indent / lug formed on the bottom surface of the recess, the upper surface of the raised portion, or the tire widthwise side surface of the land portion is formed at a predetermined distance from the outer circumference of this surface where the first indent / lug is formed. Pneumatic tire. 2. The pneumatic tire according to claim 1, wherein the recessed portion or the raised portion is formed to extend and inclined with respect to a normal to the tire circumferential direction. 7. The pneumatic tire according to claim 6, wherein the concave portion or the raised portion has an inclination angle θ set in a range of 5 ° ≦ θ ≦ 60 ° with respect to a tangent in the tire circumferential direction. 2. The pneumatic tire according to claim 1, wherein each of the recesses or risers is formed to have an acute end oriented in the tire rotation direction. The first indent / lug formed in the bottom surface of a recess, the upper surface of a raise part, or the tire width direction side surface of a land part is an angle set in the range of 0 degrees <= 60 degrees with respect to a tire radial direction. Pneumatic tire having (α). The pneumatic tire according to claim 1, wherein said sipe is formed in a zigzag shape for use on ice roads and snow roads. A tire mold comprising a tread molding portion in which the tread of the pneumatic tire according to claim 1 is molded. Forming raw tires, Mounting the raw tire on the tire mold according to claim 11, Attaching the green tire to the tire mold while extending the green tire out of the tire radial direction, and A method of manufacturing a pneumatic tire, comprising the step of heating the raw tire so that vulcanization occurs.

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